US7910284B2 - Materials for photoresist, photoresist composition and method of forming resist pattern - Google Patents
Materials for photoresist, photoresist composition and method of forming resist pattern Download PDFInfo
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- US7910284B2 US7910284B2 US11/838,951 US83895107A US7910284B2 US 7910284 B2 US7910284 B2 US 7910284B2 US 83895107 A US83895107 A US 83895107A US 7910284 B2 US7910284 B2 US 7910284B2
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- 0 C*C.C1=CC=C(C(C2=CC=CC=C2)C2=CC=CC=C2)C=C1.C1=CC=C(C(C2=CC=CC=C2)C2=CC=CC=C2)C=C1.CO[Y].CO[Y].CO[Y].CO[Y].CO[Y].CO[Y].[11*]C.[12*]C.[13*]C.[14*]C.[15*]C.[16*]C.[17*]C.[18*]C.[19*]C.[20*]C.[21*]C.[22*]C.[23*]C.[24*]C.[25*]C.[26*]C.[27*]C.[28*]C Chemical compound C*C.C1=CC=C(C(C2=CC=CC=C2)C2=CC=CC=C2)C=C1.C1=CC=C(C(C2=CC=CC=C2)C2=CC=CC=C2)C=C1.CO[Y].CO[Y].CO[Y].CO[Y].CO[Y].CO[Y].[11*]C.[12*]C.[13*]C.[14*]C.[15*]C.[16*]C.[17*]C.[18*]C.[19*]C.[20*]C.[21*]C.[22*]C.[23*]C.[24*]C.[25*]C.[26*]C.[27*]C.[28*]C 0.000 description 8
- OBJPRYAFNLFTJF-UHFFFAOYSA-H CC1=CC(O[Y][Y][Y][Y])=C(C2CCCCC2)C=C1C(C1=CC(C2CCCCC2)=C(O[Y][Y][Y][Y][Y])C=C1C)C1=CC(CC2=CC(C(C3=C(C)C=C(O[Y])C(C4CCCCC4)=C3)C3=C(C)C=C(O[Y][Y][Y])C(C4CCCCC4)=C3)=C(O[Y][Y])C=C2)=CC=C1O[Y][Y][Y][Y][Y][Y] Chemical compound CC1=CC(O[Y][Y][Y][Y])=C(C2CCCCC2)C=C1C(C1=CC(C2CCCCC2)=C(O[Y][Y][Y][Y][Y])C=C1C)C1=CC(CC2=CC(C(C3=C(C)C=C(O[Y])C(C4CCCCC4)=C3)C3=C(C)C=C(O[Y][Y][Y])C(C4CCCCC4)=C3)=C(O[Y][Y])C=C2)=CC=C1O[Y][Y][Y][Y][Y][Y] OBJPRYAFNLFTJF-UHFFFAOYSA-H 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N OC1=CC=CC=C1 Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C39/00—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring
- C07C39/12—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring polycyclic with no unsaturation outside the aromatic rings
- C07C39/17—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring polycyclic with no unsaturation outside the aromatic rings containing other rings in addition to the six-membered aromatic rings, e.g. cyclohexylphenol
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C39/00—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring
- C07C39/12—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring polycyclic with no unsaturation outside the aromatic rings
- C07C39/15—Compounds having at least one hydroxy or O-metal group bound to a carbon atom of a six-membered aromatic ring polycyclic with no unsaturation outside the aromatic rings with all hydroxy groups on non-condensed rings, e.g. phenylphenol
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/004—Photosensitive materials
- G03F7/038—Macromolecular compounds which are rendered insoluble or differentially wettable
- G03F7/0382—Macromolecular compounds which are rendered insoluble or differentially wettable the macromolecular compound being present in a chemically amplified negative photoresist composition
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
- Y10S430/1053—Imaging affecting physical property or radiation sensitive material, or producing nonplanar or printing surface - process, composition, or product: radiation sensitive composition or product or process of making binder containing
- Y10S430/1055—Radiation sensitive composition or product or process of making
- Y10S430/106—Binder containing
Definitions
- the present invention relates to negative-tone photoresist compositions used in extremely fine processing of a semiconductor device using extreme ultraviolet light (EUV light), materials for forming patterns used in the negative-tone resist compositions, and a method of patterns on a semiconductor device fabricated by using the negative-tone photoresist compositions.
- EUV light extreme ultraviolet light
- Nanofabrication by lithography using a photoresist is performed in a semiconductor device manufacturing process.
- fine patterns with the size less than 100 nanometers are often formed.
- a wavelength of beams or rays used for exposure has been increasingly reduced from that of a KrF excimer later beam (with the wavelength of 248 nm) to that of an ArF excimer laser beam (with the wavelength of 193 nm), and now the combination of the immersion exposure technique with ArF enables fabrication at the level of 100 nanometers or below.
- the lithography technique using the extreme-ultraviolet rays (EUV light with the wavelength of 13.5 nm) or an electron beam is now under development. Now it is required to form various fine patterns including a hole pattern, an isolated line pattern, or a line-and-space, and therefore both positive-tone and negative-tone resist materials are required.
- EUV light extreme-ultraviolet rays
- an electron beam is now under development. Now it is required to form various fine patterns including a hole pattern, an isolated line pattern, or a line-and-space, and therefore both positive-tone and negative-tone resist materials are required.
- the negative-tone resist material As the negative-tone resist material, the negative-tone resist for ArF described in JP-A-2003-195502 (Patent document 1) is well known.
- This resist has a hydrophilic ⁇ -hydroxycarboxylic acid structure in a macromolecule side chain of the acrylic structure.
- intramolecular esterification occurs in the ⁇ -hydroxycarboxylic acid moiety due to an effect of an acid generated from an acid generator, and the hydrophilic characteristic is changed to the hydrophobic one. Therefore, after development using an alkaline developer, the exposed portion becomes insoluble, and a negative-tone pattern is generated.
- Patent document 2 describes resist containing a non-polymer molecule as a main ingredient, and the molecule can provide high resolution and low LER, and has four or more reactive sites which are reactive moieties for the polarity-change reaction.
- LER When a resist composition based on a macromolecule is used, irregularities with the size at the order of several nanometers corresponding to the macromolecule size always appear on a side wall of a pattern, and the irregularity is referred to as LER.
- the LER becomes relatively more visible, and achievement of required processing accuracy has become more and more difficult.
- the gate length is 20 nanometers or below, and the required processing accuracy is within 10% of the dimension.
- the nanofabrication as described above is actually impossible, because the resist material based on a macromolecule described in Patent document 1 include a large-size macromolecule as a main ingredient.
- Patent document 2 includes descriptions concerning a chemical amplification-based negative-tone resist using a low-molecular-weight compound and not causing increase in a molecular weight caused on lactonization which is an intra-molecular esterification reaction.
- This resist has four or more carboxyl groups per molecule, but the number of carboxyl group is large, sometimes carboxyl groups belonging to different molecules respectively form a stable dimer, which disadvantageously causes lactonization by acidic catalyst. Therefore, post exposure baking (PEB) at a high temperature is required for forming a pattern, and when PEB is performed at a high temperature, the diffusion length of an acid becomes larger, which disadvantageously lowers the resolution.
- PEB post exposure baking
- the present inventors found that the problems relating to the extremely fine processing of semiconductors and to the photoresist compositions used in the processing can be solved by using the materials for photoresist and the negative-tone photoresist compositions using the materials.
- a configuration of the present invention is as described below.
- a material for photoresist according to the present invention is expressed by chemical formula (1) below, and is a mixture of compounds having, in one molecule, zero to six functional groups which are chemically converted due to an action of an acid with the reduced solubility in an alkaline developer.
- the material has a structure in which two or more triphenyl methane structures are bonded in the nonconjugated state to a section other than the functional groups, and each of the functional groups is bonded to a phenolic hydroxy group of a polynuclear phenol compound (a), and a weight ratio of the polynuclear phenol compound (a) not having functional group per molecule is 15% or below, while a weight ratio of the polynuclear phenol compound (a) having three or more functional groups per molecule is 40% or below. Furthermore an average number of the functional groups in one molecule of the polynuclear phenol compound (a) is 2.5 or below.
- Y denotes a functional group which is chemically converted due to action by a proton or an acid with the reduced solubility in an alkaline developer
- R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , R 23 , R 24 , R 25 , R 26 , R 26 , and R 27 are a hydrogen atom or groups selected from the group consisting of a hydrocarbon and alkyl groups or aromatic hydrocarbon groups having 1 to 10 carbon atoms.
- a structure of a phenolic nuclear is defined as a unit structure equivalent to a structure of a phenol molecular expressed by chemical formula (5):
- the polynuclear phenol is a compound having a plural phenolic nuclear structures in one molecule thereof.
- the polynuclear phenol compound has the problems that, when the molecular weight is too small, the volatility becomes disadvantageously high, and that, when the volatility is too high, an amorphous film cannot be formed.
- a molecular weight of the polynuclear phenol compound is preferably in the range from about 500 to about 2500.
- the polynuclear phenol compound in which two or more triphenyl methane structures are bridged with the nonconjugated structure expressed by chemical formula (6) is advantageously used.
- R 11 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 20 , R 21 , R 22 , R 23 , R 24 , R 25 , R 26 , R 26 , and R 27 are a hydrogen atom or groups selected from the group consisting of a hydrocarbon and alkyl groups or aromatic hydrocarbon groups having 1 to 10 carbon atoms.
- a polynuclear phenol compound expressed by chemical formula (7) is advantageously used.
- the nonconjugated structure bonding a plurality of triphenyl methane structures to each other is preferably a straight or branched alkyl group such as methylene, ethylene, and propylene, or a fatty chain alkyl group.
- the a functional group which is chemically converted due to action by a proton or an acid with the solubility in an alkaline developer included in the material for photoresist according to the present invention is a functional group which can be changed from the polar state to the not-polar state.
- a representative example of the polar group is preferably a ⁇ - or ⁇ -hydroxy carboxylic acid, and a representative example of the not-polar group is preferably ⁇ - or ⁇ -lactone generated when the polar group is esterified.
- the ⁇ -hydroxy carboxylic acid has the structure expressed by chemical formula (2).
- the ⁇ -hydroxy carboxylic acid has the structure expressed by chemical formula (3).
- each of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Further any one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 is bonded to a hydroxyl group in the polynuclear phenol in the form of ether bond.
- any of the structures expressed by chemical formulae (31) to '37) is used.
- R 31 to R 66 are alkyl groups having 1 to 6 carbon atoms.
- the material for photoresist according to the present invention can be prepared through an etherification reaction between a polynuclear phenol compound having a structure in which 2 or more triphenyl methane structures are coupled in the nonconjugated structure and ⁇ -halo- ⁇ -butyrolactone or -halo- ⁇ -valerolactone (first step) and an alkaline hydrolysis reaction (second step).
- the etherification reaction in the first step can be performed by heating the reaction materials in an organic solvent such as diethyl ether, THF, or acetone and in the presence of a strong base such as sodium hydride, potassium hydride, sodium hydroxide, lithium hydroxide, sodium carbonate, or potassium carbonate.
- the alkaline hydrolysis reaction in the second step can be performed by dissolving the product from the first step in a solvent such as acetone, diethyl ether, THF, or 1,4-dioxane and adding a basic aqueous solution of sodium hydroxide, potassium hydroxide, sodium hydrogen carbonate, sodium carbonate, tetramethyl ammonium hydroxide, or tetraethyl ammonium hydroxide.
- a solvent such as acetone, diethyl ether, THF, or 1,4-dioxane
- the etherification reaction performed for obtaining the materials for photoresist according to the present invention has low selectivity, and the reaction occurs at random in the probability to a plurality of hydroxyl groups in the polynuclear phenol compound used in the reaction, and therefore a plurality of products having different ratios respectively are obtained.
- an amount of a polar group introduced into the polynuclear phenol with the reduced solubility in an alkaline developer due to action by an acid (referred to an etherification ratio herein) is accessed by an average value of the products in the two-stage synthesis method described above, and the average value is preferably 3 or below because of the desired properties of the photoresist. More preferably the etherification ratio is in the rang from 1 to 2.5.
- the reason is as described below.
- the first reason is that, when the etherification ratio is less than 1, there are large amount of the raw polynuclear phenol compounds, in which the solubility to an alkaline developer is not lowered due to actions of an acid and the etherification ration is substantially zero, and the sensitivity or resolution becomes disadvantageously lower.
- the second reason is that, when the etherification ratio is higher than 3, there are products with the functional groups (such as a carboxyl group) having high solubility in an alkaline developer, and therefore the development speed becomes excessively high. In this case, it is required to dilute the developer at a high ratio, or the sensitivity or the resolution lowers, which is disadvantageous.
- the etherification ratio (the number of functional groups bonded to a polynuclear phenol compound) is in the range from 1 to 2.5 on average, and that a weight ratio of the compounds having the etherification ratio of zero is 15% or below and a weight ratio of the compounds having the etherification ratio of 3 or more is not more than 40%.
- the reaction is performed so that the etherification ratio is in the range from 1 to 2.5, the raw material with the etherification ratio of zero (3M6C-MBCA) is present in the total weight of the products by 20% or more, and also the products with the etherification ratio of 3 or more are present.
- the products obtained in the reaction condition for the etherification ratio of 1.0 includes the raw material with the etherification ratio of zero (3M6C-MBCA) by 36%.
- a desired material for photoresist can be obtained by providing a step of separation and purification of a product of the etherification reaction between the first and second steps.
- Chromatography is employed in this separation step.
- the chromatography is a technique for separating various components mixed in a sample by moving the sample placed at an end of a solid phase (a solid or a liquid) in an appropriate eluent (moving phase) and separating the components from each other by making use of the moving speeds of the components reflecting differences in absorbability or distribution coefficient of the components.
- the column chromatography is preferably used, and in this technique, alumina or a silica gel, which is a solid phase, is filled in a vessel referred to as column, and separation of sample components is performed in a single or a mixed organic solvent such as toluene, xylene, heptane, diethyl ether, chloroform, butyl acetate. It is possible to reduce ratios of the compounds with the etherification ratio of zero and those with the etherification ratio of 3 or more from the products obtained in the first step for obtaining the materials for photoresist according to the present invention.
- the solubility of the compounds in an alkaline developer is reduced by the mechanisms shown by the chemical formula (9-1) or (9-2). Specifically, dehydration occurs between a carboxyl group and an alcoholic hydroxyl group in the same molecule to effect the intra-molecular esterification (lactonization). The functional group is converted from a polar structure promoting solubility in an alkalinene developer to a not-polar structure not promoting the solubility in an alkaline developer.
- Chemical formula 9 shows the representative example. In the other hydroxy carboxylic acid expressed by chemical formula (7), the dehydration between a carboxyl group and an alcoholic hydroxy group occurs. As a result, the solubility in an alkaline developer is reduced. At least one ⁇ - or ⁇ -hydroxy carboxylic acid structure is required for one molecule.
- R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 denotes a hydrogen atom or an alkyl group having 1 to 10 alkyl groups. Furthermore, any one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , and R 8 is bonded to a hydroxy group in a polynuclear phenol by means of ether bond.
- the material for photoresist according to the present invention can be used as a negative-tone resist composition by dissolving the material together with an acid generator, which generates an acid with irradiated by a radiation.
- the composition according to the present invention is dissolved in a solvent containing the components described above, and is applied onto a supporting body.
- the solvents which can be used in the present invention, includes ethylene dichloride, cyclohexane, cyclopentanone, 2-heptanonw, ⁇ -butyrolactone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monomethyl ether, 2-methoxyethyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether propionate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl methoxypropionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, N,N-di
- the linear ketone having 6 to 9 carbon atoms includes 2-heptanone, 2-octanone, and the like.
- the photoresist composition according to the present invention is dissolved in a solvent, and then is preferably filtered to remove insoluble materials.
- the filter used in the process is selected from generally used in the field of photoresist.
- Any compound may be used as a photo-acid generator used in the photoresist composition according to the present invention on the condition that the compound generates an acid when irradiated by an electron beam, ultraviolet rays, X-ray, or the like.
- the compound is selected from onium salt compounds (sulfonium salt compounds, iodonium salt compounds), sulfonium imide compounds, sulfonium methyde compounds, organic halide compounds, sulfonic acid ester compounds, sulfonate compounds, and the like as shown in FIG. 1A-1L and FIG. 2A-2P .
- onium salt compounds sulfonium salt compounds, iodonium salt compounds
- sulfonium imide compounds sulfonium methyde compounds
- organic halide compounds organic halide compounds
- sulfonic acid ester compounds sulfonate compounds
- a content of the photo-acid generator in the photoresist composition according to the present invention as expressed with a weigh ratio of the photo-acid generator against the photoresist composition is in the range from 1% to 30%, and more preferably in the range from 5% to 20%.
- a content of the photo-acid generator is too small, there occurs the problem that the sensitivity is low, or that patterning cannot be performed.
- a content of the photo-acid generator is too large, there occur the problems, for example, that formed patterns degrade, that the line edge roughness increases, and that the resolution becomes lower.
- a basic quencher compound may be added in the negative-tone resist composition according to the present invention for the purpose to improve the resolution.
- the diffusion of the quencher compound is observed as a distribution of the acid component.
- the basic quencher compound which may be used in the present invention should be more basic as compared to phenols.
- a nitrogen-containing basic compound is especially preferable.
- the structures shown in FIG. 3A to 3E are examples of preferable compounds.
- R 1250 , R 1251 , and R 1252 are identical to or different from each other, and are hydrogen atom, an alkyl group having 1 to 6 carbon atoms, amino alkyl group having 1 to 6 carbon atoms, a hydroxy alkyl group having 1 to 6 carbon atoms, or a substituted or not-substituted aryl group having 6 to 20 carbon atoms.
- R 1251 and R 1252 may be bonded to each other to form a ring.
- R 1253 , R 1254 , R 1255 , and R 1256 may be identical to or different from each other, and denote alkyl groups each having 1 to 6 carbon atoms respectively.
- Preferable examples include substituted or not-substituted guanidine, substituted or not-substituted amino pyridine, substituted or not-substituted amino alkyl pyridine, substituted or not substituted amino pyrrolidine, substituted or not-substituted imidazole, substituted or not substituted pyrazole, substituted or not-substituted pyridine, substituted or not-substituted pyrimidine, substituted or not-substituted purine, substituted or not-substituted substituted imidazolyn, pyrazoline, substituted or not-substituted substituted piperazine, substituted or not-substituted amino morpholyne, and substituted or not-substituted amino alkyl morpholyne.
- Especially preferable compounds include, but not limited to, guanidine, 1,1-dimethyl guanidine, 1,1,3,3-tetramethyl guanidine, 2-amino pyridine, 3-amino pyridine, 4-phenyl pyridine, 4-amino pyridine, 2-dimethylamino pyridine, 4-dimethylamino pyridine, 2-diethylamino pyridine, 2-(amino methyl)pyridine, 2-amino-3-methyl pyridine, 2-amino-4-methyl pyridine, 2-amino-5-methyl pyridine, 2-amino-6-methyl pyridine, 3-aminoethyl pyridine, 4-aminoethyl pyridine, 3-amino pyrrolydine, piperazine, N-(2-aminoethyl)piperazine, N-(2-aminoethyl)pyperidine, 4-amino-2,2,6,6-tetramethyl pyperidine,
- the nitrogen-containing basic compounds may be used singly or in combination.
- a use rate of the nitrogen-containing basic compound against all of the components of the composition according to the present invention should be in the range from 0.001 to 10 weight %, and is preferably in the range from 0.01 to 2 weight %.
- the content is less than 0.001 weight %, the effect of addition of the composition cannot be obtained.
- the content is more than 2 weight %, there occurs that the sensitivity lowers or that the resolution in a not-exposed section becomes disadvantageously lower.
- the fluorine-based and/or silicon-based surfactant includes a fluorine-based surfactant, a silicon-based surfactant, and a surfactant containing both a fluorine atom and a silicon atom.
- the fluorine-based surfactants or silicon-based surfactants available in the present invention include F-top EF301, EF303 (produced by Shin Akita Kasei (K. K.)), Fluorad FC430, 431 (produced by Sumitomo 3M Co. Ltd), Megafac F171, F173, F176, F189, F08 (produced by DAINIPPON INK AND CHEMICALS INCORPORATED), Surflon S-382, SC-101, 102, 103, 104, 105, 106 (Produced by Asahi Glass Co., Ltd.), Troysol S-366 (Tryo Chemicals Co. Ltd.).
- polysiloxane polymer KP-341 (produced by Shin-Etsu Chemical CO., Ltd.) can be used as a silicon-based surfactant.
- a blending quantity of the surface surfactant relative to a solid content of all compositions in the composition according to the present invention is generally in the range from 0.001 to 0.5 weight %, and more preferably in the range from 0.002 to 0.1 weight %.
- Surfactants other than the fluorine-based and/or silicon-based surfactants may be used in the present invention.
- nonion-based surfactants including polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether; polyoxyethylene alkylallyl ether such as polyoxyethylene octylphenol ether, and polyoxyethylene nonylphenol ether; polyoxyethylene propylene block copolymer; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate; polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan laurate, polyoxyethylene sorbitan palmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate;
- crylic acid-based or methacrylic acid-based (co)polymerized Polyflow No. 75, No. 95 produced by Kyoueisha Fatty Chemical Industry Co. Ltd.
- a blending quantity of the other type of surfactant relative to all of the solid components in the composition according to the present invention is generally 2 weight % or below, and more preferably 0.5 weight % or below. These surfactants may be used singly or in combination.
- Effects provided by addition of a surfactant include improvement in compatibility between the photoresist composition according to the present invention and a photo-acid generator and reduction in irregularities on an applied surface.
- a method of forming resist patterns using the negative-tone photoresist composition according to the present invention comprises a step of applying the negative-tone resist composition on a matrix to obtain a resist layer, a step of irradiating a radiative ray to the resist layer, and a step of developing the resist layer irradiated by the radiation.
- the radiation the ArF laser light (with the wavelength of 193 nm), EUV light (with the wavelength of 13.5 nm), or X-ray may be used.
- the acid-generator is preferable sensitive to the radiation irradiated to the resist layer.
- an alkaline aqueous solution of any of the following compounds inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate; primary amines such as ethylamine, and n-propylamine; ammonia water; secondary amines such as diethylamine, di-n-butylamine; tertiary amines such as triethylamine, and methyl diethyl amine; alcohol amines such as dimethylethanolamine, and triethanolamine; quarternary ammonium salts such as tetramethyl ammonium hydroxide, and tetraethyl ammonium hydroxide; and cyclic amines such as pyrrole, and pyperidine.
- inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate
- primary amines such as ethylamine, and n-propylamine
- ammonia water secondary amines such as diethylamine, di-n
- an appropriate quantity of alcohols or a surfactant may be added in the alkaline aqueous solution. It is preferable to use an aqueous solution of tetramethyl ammonium hydroxide with the concentration in the range from 0.05 to 10 weight %. When the concentration is less than 0.05%, the resist film is not dissolved. When the concentration is 10% or more, sensitivity of the resist remarkably may drop, a form of prepared pattern may degrade, or any pattern may not be formed.
- FIG. 1A-1L are views illustrating a chemical formula of an acid generator used in an embodiment of the present invention.
- FIG. 2A-2P are views illustrating a chemical formula of an acid generator used in an embodiment of the present invention.
- FIG. 3A-3E are views illustrating a chemical formula of a basic compound used in an embodiment of the present invention.
- FIG. 4 is a view illustrating a composition distribution of a material for photoresist A 1 after column chromatography
- FIG. 5 is a view illustrating a composition distribution of a material for photoresist A 2 after column chromatography
- FIG. 6 is a view illustrating a composition distribution of a material for photoresist A 3 after column chromatography
- FIG. 7 is a view illustrating a 1H-NMR spectrum of the material for photoresist A 1 ;
- FIG. 8 is a view illustrating an FT-1R spectrum of the material for photoresist A 1 .
- polynuclear phenolic compound 3M6C-MBSA 15 g
- potassium carbonate (7 g) 7 g
- acetone solution 50 ml
- a solution prepared by adding a-bromo- ⁇ -butylolactone (4.0 g) in acetone solution (50 ml) was added to the mixture at the room temperature, and the mixed solution was stirred for two hours at the temperature of 45 degrees C.
- High-performance liquid chromatography (HPLC) analysis was performed to find that the etherification rate is 1.1 per molecule on average, and specifically, a percentage of compounds having the etherification rate of 1 was 33%, a percentage of compounds having the etherification rate of 2 was 20%, a percentage of compounds having the etherification rate of 3 was 7%, and a percentage of compounds having the etherification rate of 4 was 2%.
- the resultant compound in the first step was dissolved into ethyl acetate (20 ml), and the compound was separated by the column chromatography, with silica gel as a bonded phase and a mixed solvent including diethyl ether and ethyl acetate as an extraction solvent.
- the eluate was isolated by 20 ml, and compositions of the recoverable compounds for each fraction were analyzed by HPLC. An appropriate quantity of each fraction was recovered, the solvent was removed by concentration and vacuum-dried, and etherified compound of the polynuclear phenol 3M6C-MBSA (6 g) was obtained, the composition of which is shown in FIG. 4 .
- the etherification rate is 1.1 on average, and specifically, a percentage of compounds having the etherification rate of 0 was 2.5%, a percentage of compounds having the etherification rate of 1 was 85%, a percentage of compounds having the etherification rate of 2 was 10%, and a percentage of compounds having the etherification rate of 3 was 2.5%.
- ether compound of the polynuclear phenol 3M6C-MNSA (6 g) which was separated and purified by the column chromatography was dissolved in THF (100 ml).
- TMAH aqueous solution was added to the resultant solution, until pH of the solution was adjusted to 2.38%.
- the solution was stirred for 2 hours at the room temperature, THF was removed by evapolation under the reduced pressure, ethyl acetate (200 ml) was added, 1% of hydrochloric acid was added until the pH was adjusted to about 5, while stirring vigorously.
- FIG. 7 illustrates 1H-NMR spectrum of A 1 , and the signs a, b, and c denotes the spectrum assignment for the ⁇ -hydroxycarboxylic groups.
- the protons were 1 to 1.4 ppm for the methyl group, 1.6 to 1.8 ppm for the cyclohexyl group, and 6.6 to 7.0 ppm for the benzene ring.
- FIG. 8 shows FT-IR spectrum of A 1 .
- a major compound of A 1 is a composition having the etherification rate of 1, and as a result of the structure analysis by the measurement for Nuclear Overhauser Effect (NOE) of the 2-D NMR and proton NMR, the compound was determined as a mixture of compounds having different etherification positions.
- NOE Nuclear Overhauser Effect
- the etherification rate was 2.2 on average, and specifically, a percentage of compounds having the etherification rate of 0 was 0.9%, a percentage of compounds having the etherification rate of 1 is 5%, a percentage of compounds having the etherification rate of 2 is 75%, a percentage of compounds having the etherification rate of 3 is 15%, and a percentage of compounds having the etherification rate of 4 or more is 4.1%.
- the composition of A 3 is shown in FIG. 6 .
- the etherification rate was 1.6 on average, and specifically, a percentage of compounds having the etherification rate of 0 was 3%, a percentage of compounds having the etherification rate of 1 is 54%, a percentage of compounds having the etherification rate of 2 was 30%, a percentage of compounds having the etherification rate of 3 was 10%, and a percentage of compounds having the etherification rate of 4 or more was 3%.
- the resultant compound in the first step was dissolved into ethyl acetate (20 ml), and the compound was separated by the column chromatography, with silica gel (300 g) as a bonded phase and an eluent including diethyl ether and ethyl acetate as an expansion solvent.
- An eluate was isolated by 20 ml, and compositions of the recoverable compounds for each fraction were analyzed by HPLC. An appropriate amount of each fraction was recovered, the solvent was removed by concentration and vacuum-dried, and etherified compound of the polynuclear phenol 3M6C-MBSA (5.8 g) was obtained, the composition of which is shown in FIG. 7 .
- the etherification rate was 1 on average, and specifically, a percentage of compounds having the etherification rate of 0 was 0.3%, and a percentage of compounds having the etherification rate of 3 or more was 11%.
- a second step for alkaline hydrolysis
- the ether compound of the polynuclear phenol X1 (5.8 g) having been subjected to separation and refinement by the column chromatography was dissolved into THF (100 ml).
- TMAH tetramethyl ammonium hydroxide
- ethyl acetate 200 ml was added and 1% hydrochloric acid aqueous solution until pH was adjusted to about 5 with heavy stirring.
- the organic layer was washed with water and saturated NaCl aqueous solution, dried with sodium sulfate, and concentrated to obtain the compound A 4 (5.2 g) for the photoresist.
- the number of introduced ⁇ -hydroxycarboxylic acid calculated by HPLC was identical to the etherification rate calculated after the step for the separation and purification, because no ether bond decomposition occurred in this step.
- the material for photoresist A 1 , 100 weight portions, and 5 weight portions for triphenyl sulfonium triflate acid generator synthesized in the first embodiment were dissolved into weight 500 for propylene glycol monomethyl ether acetate (PGMEA), filtered by the filter having the diameter of 0.20 micrometers to obtain a solution of the photoresist compound.
- PGMEA propylene glycol monomethyl ether acetate
- the photoresist solution was spin-coated to a silicon substrate processed with hexamethyl disilazane, subjected for a thermal processing for two minutes at the temperature of 100° C., and a resist film having the thickness of 0.20 micrometers was formed.
- a line and space pattern is drawn on the resist film on the substrate with an electron beam lithography system with the acceleration voltage of 50 kV at an irradiation dose of 10 ⁇ C/cm 2 .
- the resist film was subjected to thermal processing for 5 minutes at the temperature of 100° C. to promote lactonization for reducing the solubility of a latent image portion of the resist in an alkaline aqueous solution.
- the resist film with the latent image formed thereon was developed for 60 seconds with a 2.38 weight % aqueous solution of tetramethyl ammonium hydroxide to obtain a negative-tone resist pattern.
- a cross-sectional form of the line and space pattern with the thickness of 40 nanometers was observed with an scanning electron microscope. As a result, it was recognized that the resist pattern was rectangular and the resolution was high.
- a quantity of decrease of the film thickness after development is 5 nanometers or less.
- the line edge roughness (LER) value obtained from a cross-sectional SEM image of the 100 nanometers line and space pattern obtained after development was 3 nanometers.
- the resist composition was prepared in the completely same way excluding the point that A 2 was used as a material for the photoresist, and electron beam drawing was performed by the same method and under the same conditions.
- a 40-nm line and space pattern having an excellent form could be formed at the irradiation dose of 15 ⁇ C/cm 2 .
- the line edge roughness (LER) value was obtained from a length measurement SEM image of the 100 nm line and space pattern obtained after development, and the value was 3 nm.
- a 3 or A 4 was used as a material for photoresist, a 40 nm line and space pattern having an excellent form could be formed in the same way, and the line edge roughness (LER) value was obtained from a length measurement SEM image of the 100 nm line and space pattern obtained after development, and the value was 3 nm.
- LER line edge roughness
- the resist solution obtained as described above was spin-coated to a silicon substrate processed with hexamethyl disilazane, and the silicon substrate was heated for 2 minutes at 100 degrees C. after application of the resist solution to form a resist film with the thickness of 0.10 ⁇ m.
- EUV light was irradiated from an EUV exposure tool at the irradiation dose of 10 mJ/cm 2 to draw a line and space pattern on the resist film.
- the photoresist pattern was subjected to thermal processing for 5 minutes at the temperature of 100 degrees C. to promote the lactonization for reducing solubility of a latent image section of the photoresist pattern in an alkaline aqueous solution.
- the photoresist film with a latent image formed thereon was developed for 40 seconds with an aqueous solution of tetramethyl ammonium hydroxide with the concentration of 2.38% by weight to obtain negative-tone resist patterns.
- Patterns were formed by using A 2 , A 3 , and A 4 each as a material for photoresist pattern, and 30 nm line and space patterns having an excellent form could be formed at the sensitivity of 9 to 13 ⁇ C/cm 2 .
- the film depletion rate after development was 2 nm or below.
- the line edge roughness (LER) value obtained from the length measurement SEM image of the 100 nm line and space pattern obtained after development was 2 nm.
- the first step (etherification), separation and purification by the column chromatography, and the second step were performed line in the first embodiment to obtain a material for photoresist A 5 .
- the average etherification ratio was 1.3, and a percentage of compounds with the etherification ratio of zero was 8%, a percentage of compounds with the etherification ratio of 1 was 64%, a percentage of compounds with the etherification ratio of 3 was 8%, and a percentage of compounds with the etherification ratio of 4 was 2%.
- a resist liquid was prepared like in the third embodiment and the sixth embodiment excluding the point that the material for photoresist A 5 was used, and patterning was performed with an electron beam and EUV light. In any of the cases described above, it was confirmed that the sensitivity was excellent in any case and the resolution of 50 nm or below and LER of 3 nm can be achieved.
- a material for photoresist B 1 was obtained in the same method as that employed for synthesizing the material for photoresist A in the first embodiment excluding the point that only the separation and purification step by means of the column chromatography was omitted.
- the composition of the material B 1 was checked, before hydrolysis thereof, by HPLC, and a percentage of X1 with the etherification ratio of zero was 37%, a percentage of the compounds with the etherification of 1 was 33%, a percentage of the compounds with the etherification of 2 was 20%, and a percentage of the compounds with the etherification of 4 was 2%. No change was observed in the composition expressed by the etherification ratio even after hydrolysis with an alkaline liquid.
- the resist liquid described above was spin-coated onto a silicon substrate processed with hexamethyl disilazane. After application of the resist liquid, the silicon substrate was heated for 2 minutes at 100 degrees C. to form a resist film with the thickness of 0.20 ⁇ m. A line and space pattern was drawn on this substrate with an electron beam lithography system operating at the acceleration voltage of 50 kV and at the irradiation dose of 30 ⁇ cm 2 .
- the resist pattern was subjected to thermal processing for 5 minutes at 100 degrees C. to promote lactonization for reducing the solubility of a latent image portion of the resist pattern in an alkaline aqueous solution. After the thermal processing, the resist film with a latent image formed thereon by using an aqueous solution of tetramethyl ammonium hydroxide with the concentration of 2.38% by weight was developed for 60 minutes to obtain a negative-tone resist pattern.
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- General Physics & Mathematics (AREA)
- Materials For Photolithography (AREA)
- Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Description
- 700: Materials for photoresist A1
- 710: Integral curve
- 720: Spectrum
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JP2006267830A JP4245179B2 (en) | 2006-09-29 | 2006-09-29 | PATTERN FORMING SUBSTRATE, NEGATIVE RESIST COMPOSITION, AND PATTERN FORMING METHOD |
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JP4245172B2 (en) * | 2005-12-02 | 2009-03-25 | 株式会社日立製作所 | Pattern forming substrate, negative resist composition, pattern forming method, and semiconductor device |
JP5474097B2 (en) * | 2009-02-06 | 2014-04-16 | エルジー・ケム・リミテッド | Touch screen and manufacturing method thereof |
US8339542B2 (en) | 2009-06-26 | 2012-12-25 | 3M Innovative Properties Company | Passive and hybrid daylight-coupled N-stack and collapsible backlights for sunlight viewable displays |
JP2012088697A (en) * | 2010-09-21 | 2012-05-10 | Dainippon Printing Co Ltd | Resist antistatic film laminate, method for forming relief pattern, and electronic component |
KR101784049B1 (en) * | 2014-11-14 | 2017-10-10 | 롬엔드하스전자재료코리아유한회사 | Colored photosensitive resin composition and light shielding spacer prepared therefrom |
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JP2003195502A (en) | 2001-12-26 | 2003-07-09 | Hitachi Ltd | Radiation-sensitive composition, method for forming pattern and method for manufacturing semiconductor device |
WO2004012012A1 (en) | 2002-07-30 | 2004-02-05 | Hitachi, Ltd. | Method for producing electronic device |
US20070128541A1 (en) | 2005-12-02 | 2007-06-07 | Kyoko Kojima | Materials for photoresist, negative-tone photoresist composition, method of forming resist pattern, and semiconductor device |
US20080113294A1 (en) * | 2004-12-24 | 2008-05-15 | Mitsubishi Gas Chemical Company, Inc. | Compound for Resist and Radiation-Sensitive Composition |
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JP4249096B2 (en) * | 2004-02-20 | 2009-04-02 | 東京応化工業株式会社 | Substrate for pattern forming material, positive resist composition, and resist pattern forming method |
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JP2003195502A (en) | 2001-12-26 | 2003-07-09 | Hitachi Ltd | Radiation-sensitive composition, method for forming pattern and method for manufacturing semiconductor device |
WO2004012012A1 (en) | 2002-07-30 | 2004-02-05 | Hitachi, Ltd. | Method for producing electronic device |
US20060105273A1 (en) | 2002-07-30 | 2006-05-18 | Hitachi, Ltd. | Method for producing electronic device |
US20080113294A1 (en) * | 2004-12-24 | 2008-05-15 | Mitsubishi Gas Chemical Company, Inc. | Compound for Resist and Radiation-Sensitive Composition |
US20070128541A1 (en) | 2005-12-02 | 2007-06-07 | Kyoko Kojima | Materials for photoresist, negative-tone photoresist composition, method of forming resist pattern, and semiconductor device |
US7659047B2 (en) * | 2005-12-02 | 2010-02-09 | Hitachi, Ltd. | Materials for photoresist, negative-tone photoresist composition, method of forming resist pattern, and semiconductor device |
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Mitsuru Narithiro, et al.; 10-nm-Scale Pattern Delineation Using Calixarene Electron Beam Resist for Complementary Metal Oxide Semiconductor Gate Etching; Japanese Journal of Applied Physics; 2005; pp. 5581-5585; vol. 44; No. 7B. |
Yukinori Ochiai, et al.; High-resolution, High-purity Calix[n}arene Electron Beam Resist; Journal of Photopolymer Science and Technology; 2000; pp. 413-417; vol. 13; No. 3. |
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US20080081281A1 (en) | 2008-04-03 |
CN101154037B (en) | 2010-12-22 |
JP4245179B2 (en) | 2009-03-25 |
CN101154037A (en) | 2008-04-02 |
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